Refining wood into pellets and biodiesel

I just got off the phone with Dino Mili, co-founder and CEO of New Forest Industries out of Montreal, who is speaking at the International Biomass Conference & Expo in St. Louis (May 2-5) on the pulp and paper mill renaissance panel. Mili’s presentation, titled, Low Severity Process Yields Functionalized Wood Pellets and Biodiesel, intrigued me so I gave him a call to see what it is all about. I’m also moderating that panel, so I wanted to introduce myself.

The process Mili will discuss in St. Louis is hydrotorrefaction in which wood chips are cooked in a digester with water, just like the pulp industry has been doing for years he says, at about 160 degrees Celsius for an hour and a half. The hemicellulose and soluble fractions like ash and chlorides are separated out, and the lignin and cellulose portions are used for high-grade wood pellets optimized for combustion.

Mili says the resulting wood pellets are harder, more energy dense and hydrostable, since the hydrophilic fractions are removed.

The hemicellulose is separated and hydrolyzed to C5 sugars, but rather than make ethanol from these sugars that are more difficult and costly to ferment, Mili says the project reverts to more robust, homogeneous organisms to convert the C5 sugars to lipids for use to make fatty acid methyl esters (biodiesel). New Forest Industries has hired FPInnovations to help put the project together.

“The biggest issue is the conversion of the sugars to lipids,” Mili says. He says most of the organisms the project will use were originally developed for the wastewater treatment industry. Mili couldn’t give me too much information on the details because he says they are still finalizing the patent applications.

The oil properties from the converted sugars to lipids—the microbial oils—fall between those of vegetable oils and animal fats, Mili says.

Mili says he predicts 60 percent of the revenue stream from the process will come from pellet sales, while the remaining 40 percent will be equally distributed between green power and biodiesel.

On a closing note, Mili points out how the U.S. reasoning behind supporting renewable fuels is opposite of the rest of the world. “In the U.S., it’s about oil independence first, job creation second and environment third,” he says. “Everywhere else the environment comes first, followed by job creation and then lastly, oil independence.”